caches: use a faster LRUDict implementation for LRUMemoryCache

pkgs/python-packages.nix

@@ -791,6 +791,17 b' self: super: {'
       license = [ pkgs.lib.licenses.bsdOriginal ];
     };
   };
+  "lru-dict" = super.buildPythonPackage {
+    name = "lru-dict-1.1.6";
+    doCheck = false;
+    src = fetchurl {
+      url = "https://files.pythonhosted.org/packages/00/a5/32ed6e10246cd341ca8cc205acea5d208e4053f48a4dced2b1b31d45ba3f/lru-dict-1.1.6.tar.gz";
+      sha256 = "1k2lhd4dpl6xa6iialbwx4l6bkdzxmzhygms39pvf19x1rk5fm1n";
+    };
+    meta = {
+      license = [ pkgs.lib.licenses.mit ];
+    };
+  };
   "lxml" = super.buildPythonPackage {
     name = "lxml-3.7.3";
     doCheck = false;
@@ -1668,6 +1679,7 b' self: super: {'
       self."billiard"
       self."kombu"
       self."lxml"
+      self."lru-dict"
       self."mako"
       self."markdown"
       self."markupsafe"

requirements.txt

@@ -29,6 +29,7 b' jinja2==2.9.6'
 billiard==3.5.0.3
 kombu==4.2.0
 lxml==3.7.3
+lru-dict==1.1.6
 mako==1.0.7
 markdown==2.6.11
 markupsafe==1.0.0

rhodecode/lib/rc_cache/backends.py

@@ -28,8 +28,8 b' from dogpile.cache.backends import file '
 from dogpile.cache.backends import redis as redis_backend
 from dogpile.cache.backends.file import NO_VALUE, compat, FileLock
 from dogpile.cache.util import memoized_property
+from lru import LRU as LRUDict
 
-from rhodecode.lib.memory_lru_debug import LRUDict
 
 _default_max_size = 1024
 
@@ -37,12 +37,22 b' log = logging.getLogger(__name__)'
 
 
 class LRUMemoryBackend(memory_backend.MemoryBackend):
+    pickle_values = False
 
     def __init__(self, arguments):
         max_size = arguments.pop('max_size', _default_max_size)
         arguments['cache_dict'] = LRUDict(max_size)
         super(LRUMemoryBackend, self).__init__(arguments)
 
+    def delete(self, key):
+        if self._cache.has_key(key):
+            del self._cache[key]
+
+    def delete_multi(self, keys):
+        for key in keys:
+            if self._cache.has_key(key):
+                del self._cache[key]
+
 
 class Serializer(object):
     def _dumps(self, value):